Is Overdramatically a Word?

In an overdramatic manner.

Is it overdramatic or over dramatic?

adjective. Excessively dramatic or exaggerated.

Is Tattletail a real word?

The word tattletale is mostly used in the U.S. (in Britain it's more common to use telltale). It comes from the verb tattle, "report someone's wrongdoing." In the 16th century, you'd have called a tattletale a pickthank. These days, you can also use words like snitch or whistle-blower.